Publications

no significant association existed between neospora caninum titer and serostatus to leptospira serovar hardjo, icterohaemorrhagiae, or pomona in cattle on 78 dairy herds in ontario. leptospira titer increased with parity. amongst herds not vaccinated against leptospira, the proportions of herds with > or = 1 animal seropositive to serovar hardjo, icterohaemorrhagiae, or pomona were 45%, 42%, and 58%, respectively.

avidity tests can be used to discriminate between cattle that are acutely and chronically infected with the intracellular parasite neospora caninum. the aim of this study was to compare the igg avidity elisa tests being used in four european laboratories. a coded panel of 200 bovine sera from well documented naturally and experimentally n. caninum infected animals were analysed at the participating laboratories by their respective assay systems and laboratory protocols. comparing the numeric tes ...

cellular and immunological basis of the host-parasite relationship during infection with neospora caninum.

neospora caninum is an apicomplexan parasite that is closely related to toxoplasma gondii, the causative agent of toxoplasmosis in humans and domestic animals. however, in contrast to t. gondii, n. caninum represents a major cause of abortion in cattle, pointing towards distinct differences in the biology of these two species. there are 3 distinct key features that represent potential targets for prevention of infection or intervention against disease caused by n. caninum. firstly, tachyzoites a ...

twelve killer whale (orcinus orca) were hemmed in by ice floes, and nine died on the aidomari coast in the nemuro strait in rausu, shiretoko, hokkaido, japan on 8 february 2005. tissue samples collected from 8 whales were tested for neospora caninum, toxoplasma gondii, and brucella species dna by polymerase chain reaction (pcr) assay. gamma-globulin isolated from blood samples by ammonium sulfate precipitation was tested for antibodies to these pathogens by means of agglutination tests and immun ...

long-term passage of tachyzoites in tissue culture can attenuate virulence of neospora caninum in vivo.

to determine whether prolonged in vitro passage would result in attenuation of virulence in vivo, neospora caninum tachyzoites were passaged for different lengths of time in vitro and compared for their ability to cause disease in mice. groups of balb/c mice were inoculated intraperitoneally with 5 x 10(6) or 1 x 10(7) of low-passage or high-passage n. caninum tachyzoites. the mice were monitored for changes in their demeanour and body weight, and were culled when severe clinical symptoms of mur ...

the protozoa neospora caninum is an important cause of bovine abortion world-wide. the objective of this survey was to determine the distribution pattern of infectious abortion in southern brazil with special reference to n. caninum infection. a total of 161 bovine aborted fetuses from 149 farms were analysed during a 1.5 year period. the cause of abortion was identified in 51.5% of cases. overall, 23% (37/161) of the fetuses were considered to be infected with n. caninum. bacterial infection ac ...

a 7-year-old, male neutered rhodesian ridgeback dog was referred to the university of california-davis veterinary medical teaching hospital with a 4-month history of peritonitis and episodic abdominal discomfort, lethargy, and weakness. marked abdominal distension with a prominent fluid wave was noted on physical examination. cytologic analysis of the abdominal fluid indicated a septic exudate with mixed bacteria and many protozoal zoites. differentials for the identity of the protozoal zoites i ...

identification of a dithiol-dependent nucleoside triphosphate hydrolase in sarcocystis neurona.

a putative nucleoside triphosphate hydrolase (ntpase) gene was identified in a database of expressed sequence tags (ests) from the apicomplexan parasite sarcocystis neurona. analysis of culture-derived s. neurona merozoites demonstrated a dithiol-dependent ntpase activity, consistent with the presence of a homologue to the tgntpases of toxoplasma gondii. a complete cdna was obtained for the s. neurona gene and the predicted amino acid sequence shared 38% identity with the two tgntpase isoforms f ...

immunodiagnosis of besnoitia besnoiti infection by elisa and western blot.

besnoitia besnoiti, an obligate intracellular apicomplexan protozoan parasite, is the causative agent of bovine besnoitiosis. this infection may dramatically affect body condition and lead to irreversible infertility in males, resulting in important economical losses in livestock production. identification of serologically positive animals is of major relevance to elaborate appropriate measures of control. while identification of clinical cases is relatively easy to carry out, the finding of sub ...

astroglial cells in primary culture: a valid model to study neospora caninum infection in the cns.

the protozoan neospora caninum has a veterinary importance because it causes abortion in cattle and neuromuscular alterations in dogs. we infected rat astrocytes, in vitro, with different concentrations of n. caninum. astrocytes responded to infection by producing the pro-inflammatory cytokine tnf-alpha and the neurotoxic-free radical no, 24 and 72 h post-infection. these data suggest that astrocytes, which are essential for brain function, are targets for the parasite and this represents a prac ...

associations between neospora caninum specific antibodies in serum and milk in two dairy herds in scotland.

the study evaluated the use of the mastazyme elisa for quantification of neospora caninum (n. caninum) specific igg in bovine milk and examined the relationship between serum and milk antibodies in two dairy herds. the serum and milk antibodies both had bimodal distributions in each herd. this was mainly due to between cow variation: in both herds, approximately two thirds of cows were either clearly and consistently seropositive or seronegative for n. caninum with one third consistently near th ...

here, we studied the potential of neospora caninum tachyzoites to infect heifers when administered in utero by artificial insemination via contaminated semen. eighteen primiparous cyclic heifers were hormonally synchronized and artificially inseminated. nine of them, which were inseminated with semen containing 10(7) live n. caninum nc-1 isolate-tachyzoites, reacted with seroconversion and a specific ifn-gamma response. moreover, n. caninum dna was demonstrated by a nested-pcr in the blood of al ...

comparison of different methods for the solubilisation of neospora caninum (phylum apicomplexa) antigen.

parasite antigens are of interest both for the development of better diagnostic tools and potential subunit vaccines. particularly, relevant in this regard are membrane proteins as the first point of contact between host and parasite. here, four different methods for the extraction and solubilisation of neospora caninum proteins were evaluated by comparing protein yield, specific antigenicity and relative protein abundance in the electrophoresis profile. extraction with sds and sulphobetaines (s ...

a seroepidemiology study of neospora caninum was conducted in mashhad area, khorasan province, iran on 337 cattle from 30 dairy using elisa. all herds had seropositive cattle and antibodies were formed in 46% of the cattle. abortion was significantly associated with seropositivity of cattle. the highest risk of abortion was observed in the 1-2-year-old cows. our results indicate that neospora infection is widespread in iran.

validation of a commercially available celisa test for canine neosporosis against an indirect fluorescent antibody test (ifat).

a commercially available competitive enzyme-linked immunosorbent assay (celisa, vmrd) was validated for the detection of neospora caninum antibodies in the serum of dogs, using as a reference test an indirect fluorescent antibody test (ifat, fuller). a partial verification approach was used. a total of 618 dogs were screened with celisa and a subset of positive and negative sera (n=237) were then tested with ifat. naïve relative sensitivity (se(nv)) and naïve relative specificity (sp(nv)) of cel ...

here, we identify and clone the ncsag4 gene, orthologue to the toxoplasma gondii tgsag4 gene, and the first reported gene to be expressed specifically during the neospora caninum bradyzoite stage. to isolate ncsag4, we designed degenerate oligonucleotides based on the tgsag4 protein amino acid sequence. a 312-bp dna fragment was amplified by pcr from n. caninum genomic dna, whose sequence showed 65% identity to tgsag4 gene over 257 bp. ncsag4 gene sequence was obtained by pcr genome walking. nuc ...

occurrence of neospora caninum in dogs and its correlation with visceral leishmaniasis in the urban area of campo grande, mato grosso do sul, brazil.

neospora caninum is an obligate intracellular protozoan that can infect domestic and wild canids, as well as ruminants and equines, and is described as causing neuromuscular alteration and death in dogs. visceral leishmaniasis (vl) is an infectious disease that affects both humans and animals, being caused by protozoan parasites of the genus leishmania, of which leishmania (leishmania) chagasi is found in brazil -- transmitted by sand flies, such as lutzomyia longipalpis, in most of the american ...

prevalence of sarcocystis neurona and neospora spp. infection in horses from brazil based on presence of serum antibodies to parasite surface antigen.

sera from 961 horses from brazil were tested for antibodies against the major surface antigens snsag4 and nhsag1 to determine the seroprevalence of sarcocystis neurona and neospora hughesi, respectively. antibodies against snsag4 were detected in 669 (69.6%) of the horses, while antibodies against nhsag1 were detected in only 24 (2.5%) of the horses. these serologic results suggest that there is a high concentration of s. neurona in the environment of brazil, which results in marked exposure of ...

[seroprevalence of neospora caninum in cattle in the region of kayseri].

this study was carried out in order to determine the seroprevalence of neospora caninum in cattle in the region of kayseri. blood samples were collected from 186 cattle and sera were obtained from these samples. sera samples were analyzed for antibodies against n. caninum using a commercially available competitive elisa (c-elisa) kit. according to the elisa test results, seroprevalence of n. caninum in the region of kayseri was found to be 7%. three of 9 aborting cows (33.3%) were found to be se ...

neospora caninum represents one of the most frequent abortifaciant organisms worldwide. the parasite is diaplacentally transmitted from the pregnant cow to the fetus, where it normally leads to the delivery of a healthy, however persistently infected calf. abortion thus is a relative rare event. the transmission of bovine neosporosis occurs in more than 90% of the cases vertically due to the endogenous reactivation of a persistently infected mother. exogenous infections are therefore responsible ...

effect of neospora caninum-serostatus on culling, reproductive performance and milk production in dutch dairy herds with and without a history of neospora caninum-associated abortion epidemics.

we quantified the effect of neospora caninum (nc)-serostatus on culling and (re)production in 83 herds randomly selected from the dutch dairy herd population (random group) and in 17 herds that had experienced an abortion epidemic associated with nc infection (epidemic-abortion group). in the random group, a single whole-herd blood sampling was done during the spring of 2003, while in the epidemic-abortion group whole-herd blood sampling was done repeatedly at least once a year starting after th ...

simulating the impact of four control strategies on the population dynamics of neospora caninum infection in swiss dairy cattle.

a dynamic deterministic simulation model was developed to assess the impact of different putative control strategies on the seroprevalence of neospora caninum in female swiss dairy cattle. the model structure comprised compartments of "susceptible" and "infected" animals (si-model) and the cattle population was divided into 12 age classes. a reference model (model 1) was developed to simulate the current (status quo) situation (present seroprevalence in switzerland 12%), taking into account avai ...

[distribution of anti-neospora caninum antibodies in dairy cows at municipalities of resende and rio claro in the state of rio de janeiro, brazil].

this study aimed to verify the prevalence of anti-neospora caninum antibodies in dairy cows from municipalities of resende and rio claro, both located at sulfluminense dairy belt. a total of 29 farms from resende and 28 from rio claro were randomly selected. to evaluate the association between herds and animals against the etiological agent χ² tests were used. seventy eight animals at resende (25.74%, confidence intervals(ic) at 95%: 15.7-25.8%) had anti-n. caninum antibodies, while 53 animals ( ...

the prevalence of antibodies anti-neospora caninum in bovines was determined in 21 farms from anápolis and goiânia microregions, in goiás, brazil. out of these 11 were dairy farms (holstein and crossbred holstein-zebu), nine had beef cattle (nelore) and one was for mixed exploitation (simental). blood samples were collected from 930 animals, and sera obtained were separated and stored at -20 degrees c. serum samples were examined by the immunofluorescent antibody technique (ifat), using tachyzoi ...

financial analysis of various strategies for the control of neospora caninum in dairy cattle in switzerland.

the present study was conducted to estimate the direct losses due to neospora caninum in swiss dairy cattle and to assess the costs and benefits of different potential control strategies. a monte carlo simulation spreadsheet module was developed to estimate the direct costs caused by n. caninum, with and without control strategies, and to estimate the costs of these control strategies in a financial analysis. the control strategies considered were "testing and culling of seropositive female catt ...

bovine neosporosis is a parasitic disease produced by neospora caninum that induces abortion in cows, and consequently has a negative impact on the herd's reproductive efficiency. the main objective of this research was to determine the serological evidence of n. caninum in cattle herds from venezuela using an indirect antibody capture elisa test. four hundred and fifty-nine (459) serum samples from crossbred adult cows were collected to be tested for neospora antibodies. the sampled cows came f ...

one hundred twenty camels were blood-sampled and used to evaluate serological screening for neospora caninum and toxoplasma gondii infection by indirect fluorescent antibody test (ifat) in mashhad, iran, during years 2004-2005. of the 120 camels, antibodies to n. caninum were found in three in titers of 1:20 and in four in titers of 1:40 using whole n. caninum tachyzoites as ifat slide (vmrd inc., pullman, wa 99163, usa). antibodies to t. gondii were found in three camels in titers 1:20 and in t ...

detection of immunoglobulin g antibodies to neospora caninum in humans: high seropositivity rates in patients who are infected by human immunodeficiency virus or have neurological disorders.

considering that little is known about the epidemiology of neospora caninum infection in humans, particularly in populations with high toxoplasma gondii infection rates, the present study aimed to investigate the presence of antibodies to n. caninum in t. gondii-seropositive and -seronegative individuals. a total of 256 serum samples divided into four groups (61 samples from human immunodeficiency virus [hiv]-positive patients, 50 samples from patients with neurological disorders, 91 samples fro ...

natural killer (nk) cells are considered to be key players in the early innate responses to protozoan infections, primarily indirectly by producing gamma interferon (ifn-gamma) in response to cytokines, like interleukin 12 (il-12). we demonstrate that live, as well as heat-inactivated, tachyzoites of neospora caninum, a toxoplasma-like protozoan, directly trigger production of ifn-gamma from purified, il-2-activated bovine nk cells. this response occurred independently of il-12 but was increased ...

low seroprevalence of antibodies to neospora caninum in wild canids in israel.

the role of domestic dogs in the epidemiology of neospora caninum as well as the relationship between n. caninum infection of farm dogs and cattle were demonstrated, however, evidence is scarce regarding the role of wild canids in domestic animal neosporosis. the present study was undertaken to evaluate the role of wild canids in the epidemiology of bovine neosporosis in israel by analyzing the prevalence of antibodies to n. caninum in wild canids. sera samples were collected from 114 free rangi ...

neospora caninum is an apicomplexan protozoan parasite that is a significant infectious abortifacient agent in cattle. despite the fact that it is a member of a well described taxonomic group, it is a relatively newly discovered parasite and its biology is not yet fully understood. cattle become infected either congenitally via transplacental transmission or post-natally by ingesting oocysts derived from the definitive host; dogs and coyotes are the only definitive hosts that have been described ...

sarcocystis neurona, sarcocystis canis, toxoplasma gondii, and neospora caninum are related apicomplexans that can cause systemic illness in many species of animals, including dogs. we investigated one breeder's 25 basset hounds for these infections. in addition, tissues from dogs and other non-canine hosts previously reported as s. canis infections were studied retrospectively. schizonts resembling those of s. neurona, and recognized by polyclonal rabbit anti-s. neurona antibodies, were found i ...

we conducted a longitudinal study to follow-up the anti-neospora caninum serologic status in 30 initially seropositive and 83 initially seronegative cows during their pregnancy. study cows were blood-sampled every other month during pregnancy until parturition. blood serum samples were screened for anti-n. caninum antibodies by elisa. cows that seroconverted were re-tested by immunoblot as a confirmation test. among 30 seropositive cows, 28 cows remained seropositive during the whole pregnancy, ...

neospora caninum, toxoplasma gondii and encephalitozoon cuniculi are important pathogens with affinity to the central nervous system of many animals. 240 brains of wild carnivores were examined by pcr-based diagnosis. the presence of n. caninum dna was confirmed in 4.61% (7/152) red foxes (vulpes vulpes). dna of t. gondii was found in 4.92% (3/61) martens (martes sp.) and in 1.32% (2/152) red foxes. dna of e. cuniculi was determined in 3.28% (2/61) martens and in one examined european otter (lut ...

a cross-sectional study was used to test the relationship between herd seroprevalence to neospora caninum and various potential herd-level risk factors in 60 dairy farms located in two distinct regions in southern brazil. thirty farms were randomly selected from within each region. a questionnaire was designed to summarize each farm's production system as it might relate to n. caninum transmission. the questionnaire contained 105 closed questions relating to general characteristics of the farms, ...

polyclonal and monoclonal antibodies to native neospora caninum tachyzoite surface protein ncsrs2 were generated and tested in vitro for their ability to neutralize tachyzoite attachment to and invasion of host cells. host cells included vero cells and a newly cloned, immortalized ovine trophoblast cell line obtained from primary cultures of ovine placenta. the ovine trophoblasts had morphology consistent with fetal trophoblasts and expressed mrna for interferon-tau, a marker for trophoblasts. n ...

seroprevalences of antibodies to neospora caninum and toxoplasma gondii in zoo animals.

neospora caninum is an apicomplexan parasite that causes neuromuscular disease in dogs and abortions in cattle. little is known about the prevalence of antibodies to this parasite in zoo animals. sera from 556 animals, from 13 czech and slovak zoos were tested for antibodies to n. caninum and toxoplasma gondii by indirect fluorescent antibody test. antibodies to n. caninum were found in 31 of 556 zoo animals (5.6%), representing 18 of 114 species tested: eurasian wolf (canis lupus lupus), maned ...

the prevalence of neospora caninum and co-infection with toxoplasma gondii by pcr analysis in naturally occurring mammal populations.

neospora caninum and toxoplasma gondii are closely related intracellular protozoan parasites associated with bovine and ovine abortion respectively. little is known about the extent of neospora/toxoplasma co-infection in naturally infected populations of animals. using nested pcr techniques, based on primers from the nc5 region of n. caninum and sag1 for t. gondii, the prevalence of n. caninum and its co-infection with t. gondii were investigated in populations of mus domesticus, rattus norvegic ...

in this prospective study, repeated bulk milk tests were evaluated to establish the neospora caninum antibody status and to describe infection dynamics and changes in prevalence of n. caninum in thai dairy herds. bulk milk from 418 herds in northeast thailand were collected at three consecutive samplings, in december 2002 (sampling 1), april (sampling 2) and december 2003 (sampling 3). all samples were analysed for presence of n. caninum antibodies by iscom elisa, and the optical density values ...

evaluation of an iscom elisa used for detection of antibodies to neospora caninum in bulk milk.

the intracellular parasite neospora caninum is increasingly recognized as an important cause of abortion and stillbirth in cattle. presence of specific antibodies indicates infection, and the immunostimulating complex (iscom) enzyme-linked immunoassay (elisa) has previously been evaluated for use on individual milk and sera. in the present study, this test is investigated for use on bulk milk. in this study, 124 herds were used to analyse the relationship between within-herd prevalences based on ...

supranational comparison of neospora caninum seroprevalences in cattle in germany, the netherlands, spain and sweden.

herd, within-herd and animal prevalences for neospora caninum in beef and dairy cattle were compared between four countries. in randomly selected herds from regions of germany, the netherlands, spain and sweden that were representative for the cattle production of these countries, all animals > or = 2 years were examined serologically by enzyme-linked immunosorbent assays (elisas) with high test specificity (> 98.0%). in a previous study, the elisas had been validated against each other. single ...

variations of neospora caninum antibody levels in milk during lactation in dairy cows.

a longitudinal study was performed to investigate the variations of neospora caninum antibody levels in individual milk during lactation as well as the association between antibody levels in serum and milk. serum and milk samples of 15 milking cows were collected between february 2003 and september 2004 in three smallholder dairy farms in khon kaen province in northeast thailand. all samples were analyzed for presence of antibodies by an n. caninum iscom elisa test kit and the results were given ...

prevalence of anti-neospora caninum antibodies in cattle and dogs from western amazon, brazil, in association with some possible risk factors.

for evaluation of the prevalence of anti-neospora caninum antibodies and its associated risk factors, serum samples from 2109 cattle (11 beef, 50 dairy and 25 mixed farms) and 174 dogs were examined in the state of rondônia, western amazon, brazil. an inquiry was applied in each farm. sera were examined by the indirect fluorescence antibody test (ifat) using cut off dilution of 1:25 for cattle and 1:50 for dogs. statistical association between the serologic status and several variables were anal ...

in vitro isolation and characterisation of the first canine neospora caninum isolate in australia.

neospora caninum was isolated and established in vitro from the skin lesion of a naturally infected dog. the identity of the parasite was evaluated by immunofluorescent antibody test (ifat), microscopy, western blotting and polymerase chain reaction (pcr). n. caninum dna was detected in the whole blood, serum, skin lesion, rectal scrapings and faeces of the infected dog utilising a nested pcr targeting the nc-5 gene of n. caninum. antigenic and genetic characterisation of the isolate, designated ...

canine neosporosis in hungary: screening for seroconversion of household, herding and stray dogs.

in order to assess the seroprevalence of canine neosporosis 651 blood samples were collected from 586 household, 41 herding and 24 stray dogs, at small animal clinics in four large cities and other places of hungary. nineteen (2.9%) showed positivity in the ifat with titres between 1:80 and 1:10240. two dogs with high titres of antibodies to neospora caninum had neuromuscular signs (imbalance, tremor) and a further one developed papulomatous, ulcerative and necrotizing dermatitis. there was no c ...

the effect of neospora caninum, a parasite that causes abortion and neuromuscular changes, has been investigated on a major population of neural cells, the astrocytes. highly enriched astroglial primary cultures obtained from neonatal rats were infected after 21 days of culture. astroglial reactivity, il-10 and ifn-gamma expression, and cell viability (lactate dehydrogenase activity, metabolization of tetrazolium salt, and trypan blue exclusion assay) have been investigated after 24 and 72 h of ...

the aim of this study was to determine by nested pcr probe the presence of neospora caninum in fetal brain tissue from aborted dairy fetuses in aguascalientes, a state in the central part of mexico. forty-four fetal brains from eight dairy farms were analyzed using single tube nested pcr probe with primers nf1, ns2, nr1 and sr1, with histopathology as the reference technique. from the 44 bovine fetuses studied, 35 (80%) were diagnosed as being infected by n. caninum using pcr probe and 20 (45%) ...

neospora caninum is a heteroxenous cyst-forming coccidian closely related to toxoplasma gondii and is considered one of the major causes of abortions in cattle worldwide. the present work aims to update the epidemiological trend of n. caninum of dairy cattle in sardinia island, western mediterranean (italy). for this reason, we used the newest enzyme-linked immunoassay (elisa) methodology that exploits immune-stimulating complexes (iscoms) principle and allows us to point out the infection in th ...

prevalence of toxoplasma gondii and neospora caninum antibodies in wild boars in the czech republic.

sera collected from hunter-killed wild boars (sus scrofa) during 1999-2005 from seven different regions of the czech republic were assayed for antibodies to toxoplasma gondii by indirect fluorescence antibody test and to neospora caninum by competitive-inhibition enzyme-linked immunosorbent assay and by indirect fluorescence antibody test. antibodies to t. gondii were detected in 148 (26.2%) of 565 wild boars with serum dilutions of 1:40 in 40, 1:80 in 40, 1:160 in 27, 1:320 in 19, 1:640 in 18 a ...

prevalence of neospora caninum infection in australian (nsw) dairy cattle estimated by a newly validated elisa for milk.

to determine the performance characteristics of an institut pourquier (ip) enzyme-linked immunosorbent assay (elisa) for the detection of antibodies against neospora caninum in bovine milk and subsequent determination of the prevalence of n. caninum infection in new south wales (nsw) dairy cattle.

neospora caninum is a world-wide parasite that causes neuromuscular disorders in dogs and bovine abortion. biological diversity among isolates has been proved in both in vivo and in vitro studies. in contrast, little is known about the genetic diversity of this parasite. microsatellite sequence analysis constitutes a suitable tool that has been used for the genetic analysis of other apicomplexan parasites. in this report, we describe the identification and analysis of 13 microsatellite loci from ...

it has been suggested that the abortion herd pattern could influence bovine foetal neosporosis. here, a comparison of (i) neospora caninum dna-detectability by pcr, (ii) n. caninum-associated lesions and (iii) parasite loads in target organs was made between epidemic and endemic abortion cases. we observed that n. caninum dna was predominantly detected in more than one organ in the foetuses from herds with epizootic rather than endemic abortion cases (p<0.05, fisher f-test). the highest parasite ...

if control of neospora caninum infection is technically feasible does it make economic sense?

recent work on neospora caninum, a protozoan parasite that causes abortions in dairy cattle has focused on a number of different control options. modelling has suggested the most effective options for control but the present paper argues that the most effective option might not necessarily be optimal from an economic point of view. decision trees, using published quantitative data, were constructed to choose between four different control strategies. the costs of these interventions, such as 'te ...

dynamics of transcription of immunomodulatory genes in endothelial cells infected with different coccidian parasites.

sporozoites of eimeria bovis and tachyzoites of neospora caninum and toxoplasma gondii are able to invade and to replicate in endothelial cells. here we report on responses of bovine umbilical vein endothelial cells (buvec) in vitro to these coccidial infections by determining mrna levels of the cxc chemokines gro-alpha, il-8 and ip-10, the cc chemokines mcp-1 and rantes and of gm-csf, cox-2 and inos relative to the level of housekeeping gene (gapdh) transcription. t. gondii and n. caninum tachy ...

a nested pcr that successfully detected neospora caninum dna in serum of cattle was used for investigation of selected abortion cases and in a study of healthy pregnant cows at an abattoir. n. caninum dna was not detected in serum from antibody positive dams that aborted due to n. caninum, but was present in serum of some antibody negative dams that aborted due to other causes. n. caninum dna was also found in the serum of about half of the animals that aborted of undetermined cause, but was not ...

distribution of antibodies against neospora caninum, bvdv and bhv-1 among cows in brazilian dairy herds with reproductive disorders.

neospora caninum, bovine viral diarrhea virus (bvdv) and bovine herpes virus 1 (bhv-1) are worldwide spread pathogens associated with reproductive problems in cattle. the present work aimed to observe the infection pattern of these three pathogens in two dairy herds with distinct reproductive managements from triângulo mineiro, minas gerais state, brazil. the herds were not vaccinated against either n. caninum, bvdv or bhv-1. blood samples were collected and analyzed for presence of specific ant ...

vaccination as a control strategy against the coccidial parasites eimeria, toxoplasma and neospora.

the protozoan parasites eimeria spp. toxoplasma gondii and neospora caninum are significant causes of disease in livestock worldwide and t. gondii is also an important human pathogen. drugs have been used with varying success to help control aspects of these diseases and commercial vaccines are available for all three groups of parasites. however, there are issues with increasing development of resistance to many of the anti-coccidial drugs used to help control avian eimeriosis and public concer ...

seroprevalence of neosporosis in beef and dairy cattle breeds in northeast hungary.

in order to assess the seroprevalence of bovine neosporosis with indirect fluorescent antibody test (ifat), blood samples were collected randomly from 1063 beef and dairy cattle belonging to 12 different breeds in northeast hungary. antibodies to neospora caninum were detected in 27 (2.5%) of the animals, kept on 19 of the 42 settlements included in this survey. since samples were collected on 50 farms, herd prevalence amounted to 38%. the percentage of cattle with seroconversion increased with ...

the aim of this study was to examine the feces of free-ranging foxes and coyotes for the presence of neospora caninum oocysts. feces were collected from 271 foxes and 185 coyotes in the canadian province of prince edward island, processed by sucrose flotation, and examined by light microscopy for the presence of coccidian oocysts. in 2 fox and 2 coyote samples, oocysts morphologically and morphometrically similar to oocysts of n. caninum were observed. dna was extracted from these samples and su ...

comparative effect of neospora caninum infection in balb/c mice at three different gestation periods.

neospora caninum has been recognized as a major cause of infectious bovine abortion worldwide. in the present study, the effect of n. caninum infection in mice at the 3 gestation periods (first, second, and third period) was investigated. in dams, tissue distribution of n. caninum was evaluated by nested polymerase chain reaction. in the progeny, fetal mortality, stillbirth, litter size, neonatal mortality/morbidity, vertical transmission, and parasite burden in neonatal tissues were evaluated. ...

first report of neospora caninum abortion in a beef cow-calf herd from andorra, europe.

neospora caninum-associated abortion was diagnosed in a 7-mo gestational age beef cow fetus from andorra. the fetus had a multifocal necrotizing encephalitis and nonpurulent multifocal myocarditis. the diagnosis was confirmed by demonstration of n. caninum dna by polymerase chain reaction and tachyzoites by specific staining with n. caninum polyclonal antibodies in the fetal brain. the dam of the aborted fetus had serum n. caninum antibodies at the time of abortion but not 2 mo before abortion t ...

neospora caninum, sarcocystis spp, and toxoplasma gondii are related coccidian parasites that can cause abortion and neonatal mortality in animals. in addition, t gondii and certain species of sarcocystis are zoonotic. this article reviews information on the etiology, diagnosis, control, and prevention of these diseases.

use of an immunodominant p17 antigenic fraction of neospora caninum in detection of antibody response in cattle.

a neospora caninum 17 kda protein fraction (p17) has been described as an immunodominant antigen (ida) under reducing and non-reducing conditions. the aim of the present study was to investigate the diagnostic utility of p17 in cattle. in order to achieve this, p17 was purified by electroelution from whole n. caninum tachyzoite soluble extract and a p17-based western blot (wb-p17) was developed. the p17 recognition was measured by densitometry and expressed as od values to check the validity of ...

influence of the stage of pregnancy on neospora caninum distribution, parasite loads and lesions in aborted bovine foetuses.

in the present work we have studied in neospra caninum aborted bovine foetuses the influence of foetal age (first, second and third gestational periods) on parasite distribution by nested pcr, parasite loads by real-time pcr and n. caninum associated lesions. for this purpose, a total of 220 aborted foetuses were analysed and detection of n. caninum infection was accomplished by nested-pcr in brain, heart and liver, detecting the presence of the parasite in 72 (32.7%) bovine foetuses. when the d ...

sera from 800 asymptomatic horses were examined for the presence of antibodies to neospora caninum by immunofluorescence antibody test (ifat). the presence of antibodies to n. caninum was also tested in sera from 52 mares that had aborted and 40 horses exhibiting neurological signs. a total of 95 (11.9%) of the 800 sera had antibodies for neospora. significantly higher seropositivity was obtained from horses that had neurological signs (21.2%) and from aborted mares (37.5%). there was significan ...

the aim of this study was to investigate the participation of neospora caninum and toxoplasma gondii in abortion cases of peruvian llamas and alpacas. fifteen aborted foetuses were recovered from two main rearing areas of camelids in peru (central or south andean region). foetal histopathology was used to detect the presence of protozoal-associated lesions in target organs. n. caninum and t. gondii infections were confirmed by immunohistochemistry (ihc) combined with pcr and by pcr alone, respec ...

occurrence of antibodies against neospora caninum in water buffaloes (bubalus bubalis) on four ranches in corrientes province, argentina.

the aim of the present work was to describe the occurrence of antibodies to neospora caninum in water buffaloes on four ranches located in corrientes province in the northeast of argentina. antibodies against n. caninum were determined in sera of 449 water buffaloes by using an indirect fluorescent antibody test (ifat). a bayesian logistic regression mixed model was used to quantify the strength of association between positive serological results to n. caninum and gender, age and category (calf, ...

the host-parasite relationship in pregnant cattle infected with neospora caninum.

the protozoan parasite neospora caninum is an important cause of reproductive disease in cattle worldwide. the dog is a definitive host for the parasite and the oocyst stage, shed in the faeces, is a source of infection for cattle through consumption of contaminated feed or water. in addition, transplacental transmission of n. caninum is a very efficient means of the parasite infecting a new host and this can occur in successive pregnancies and over several generations. neospora parasites may ca ...

dense-granule protein ncgra7, a new marker for the serodiagnosis of neospora caninum infection in aborting cows.

to investigate whether the production of an antigen-specific antibody is associated with neospora caninum-induced bovine abortion, 62 serum samples were tested with an enzyme-linked immunosorbent assay using the recombinant antigens ncsag1, ncsrs2, and ncgra7. our study suggested that ncgra7 would be a new marker for the serodiagnosis of n. caninum infection resulting in abortion.

to clarify the role of progesterone in the development of immune responses during pregnancy against neospora caninum infection, c57bl/6 mice were given a progesterone pellet, and measured on interferon-gamma and interleukin-4 production following the infection. ifn-gamma production in the prescribed group was significantly lower than that in the intact group on day 40 post administration. il-4 producing cell population in the prescribed group was larger than that in the intact group. these resul ...

a 1.5-year-old male feist dog was presented to a veterinarian for reluctance to stand on the hind legs. treatment included dexamethasone and resulted in a favorable initial response, but posterior paresis returned and progressed to recumbency, hyperesthesia, and attempts to bite the owner. the dog was euthanized. the brain was negative for rabies by fluorescent antibody analysis. multiple foci of encephalitis were found in the cerebrum and particularly in the cerebellum. protozoa morphologically ...

neospora caninum in cattle: experimental infection with oocysts can result in exogenous transplacental infection, but not endogenous transplacental infection in the subsequent pregnancy.

whilst it is presumed that infection of pregnant cattle with neospora caninum oocysts can provoke abortion and is the likely cause of epidemic abortion outbreaks, only two previous experiments have involved inoculation of pregnant cows with oocysts (and only one abortion was provoked in 22 pregnancies). here, we describe the oral oocyst challenge of 18 cows synchronously bred and inoculated precisely at 70 (n=6), 120 (n=6) and 210 (n=6) days in pregnancy with a nominal dose of 40,000 oocysts. on ...

ninety-six of 108 randomly selected dutch dairy herds had one or more cows with a positive serostatus for n. caninum. in these 96 herds, we have quantified the probabilities of vertical transmission (vt) and horizontal transmission (ht) of n. caninum infection by combining serostatus and pedigree data in 4091 dam-daughter pairs. the probability of animals infected by vertical transmission during pregnancy (prob(vt)) was calculated as the proportion of seropositive daughters among daughters of se ...

the dynamics of antibody production against neospora caninum during the gestation period was examined in chronically infected dairy cows. data were obtained from 86 pregnant parous dairy cows, 21 of which had suffered abortion. the cows belonged to two herds in which a diagnosis of n. caninum infection had been previously confirmed in aborted foetuses. pregnancy diagnosis and blood collection were performed on post-insemination days 40, 90, 120, 150, 180, 210, and at parturition or until the tim ...

neospora caninum, an obligate intracellular protozoan parasite, is the causative agent of bovine neosporosis, an important disease affecting the reproductive performance of cattle worldwide. currently there is no effective vaccine available to prevent n. caninum infection in cattle. in this study, we examined the feasibility of developing a live, recombinant n. caninum vaccine using brucella abortus vaccine strain rb51 as the expression and delivery vector. we generated two recombinant rb51 stra ...

seventy-five house mice (mus musculus), 103 rats (rattus norvegicus) and 55 field mice (apodemus sylvaticus) from north-west italy were pcr analysed for neospora caninum infection. brain, kidney and muscle tissues collected from the above mentioned animals were tested by pcr using np6 and np21 primers. the brain tissue from 2 house mice and 2 rats, the kidney from 4 rats, 1 house mouse and 1 field mouse and muscle from 10 rats, 8 house mice and 1 field mouse were tested positive for n. caninum. ...

neospora caninum causes economical impact in cattle-raising farms since it is implicated as the major cause of bovine abortions. although infection by the parasite has been widely described in mammals, the role of birds in its life-cycle is still obscure. therefore, this work aimed to evaluate the infection by n. caninum in different chicken models. experimental infections were conducted in 7-day-old chicks, laying hens and embryonated eggs, where samples were analysed for parasite burden, igg a ...

seroprevalence of neospora caninum infection in dogs from rural and urban environments in tehran, iran.

103 serum samples were taken from owned dogs in tehran (53 urban dogs and 50 farm dogs) from february to may 2005 and tested for igg antibody against neospora caninum using the immunofluorescence antibody test. urban dogs were selected from apparent healthy dogs referred to the small animal hospital of faculty of veterinary medicine, university of tehran, for routine operation, and the farm dogs were selected from the sheepdogs in sheep flocks around tehran randomly. the titer of 1:50 was select ...

cb-17 scid and balb/c male mice were inoculated intraperitoneally with neospora caninum to examine the possibility of its venereal transmission. some of these mice were killed on days 7 and 20 post-inoculation to examine the genital organs for presence of the parasite. the remaining scid male mice were housed with non-infected female mice from day 7 p.i. and kept with them for 14 days. these scid mice died between days 28 and 35 p.i. n. caninum dna was detected in the testis of mice on days 7 an ...

the aim of this study was to compare systemic humoral immune responses in pregnant heifers inoculated with neospora caninum tachyzoites by conjunctival and intravenous routes. twenty nine heifers separated in three experimental groups were studied: group 1 (n=10 animals) and group 2 (n=9 animals) were inoculated with 10(8) of n. caninum tachyzoites by conjunctival and intravenous routes at 5th month of gestation, respectively; group 3 (n=10 animals) were non-inoculated control animals. an indire ...

cloning and expression of an antigenic domain of a major surface protein (nc-p43) of neospora caninum.

neospora caninum is an obligate intracellular protozoan that can infect domestic and wild canids, as well as ruminants and equines. it was described in 1988 as causing neuromuscular alterations and death in dogs. recently, n. caninum has been the focus of considerable attention for its large impact on the dairy industry, given the economic losses related to breeding failures and to a decrease in productivity. elisa diagnosis of neosporosis has not been widely used in brazil, mostly because of th ...

prevalence of anti-toxoplasma gondii and anti-neospora caninum antibodies in goats slaughtered in the public slaughterhouse of patos city, paraíba state, northeast region of brazil.

the prevalence of anti-toxoplasma gondii and anti-neospora caninum antibodies was investigated in goats slaughtered in the public slaughterhouse of patos, state of paraíba, northeast region of brazil, and possible associations between sex of the animals and antibody prevalence were verified. three-hundred six blood samples from goats collected before slaughter by jugular venopuncture were used. for the serologic diagnosis of t. gondii and n. caninum, the indirect fluorescent-antibody test (ifat) ...

first identification of neospora caninum infection in aborted bovine foetuses in china.

the first identification of neospora caninum infection in the tissues of aborted bovine foetuses in china is reported. aborted foetuses were collected from 16 dams, and 12 of the dams had high serum antibody titres to n. caninum determined using an elisa test kit. the nc-5 gene of n. caninum was amplified from dna samples extracted from brains of four aborted foetuses using a neospora-specific pcr assay, confirming n. caninum infection in the aborted foetuses. histology and immunohistochemistry ...

protozoal meningoencephalitis is uncommon in raptors. an adult female bald eagle (haliaeetus leucocephalus) was euthanized after several months of treatment for progressive neurologic signs. the predominant histologic lesion was lymphoplasmacytic and histiocytic meningoencephalitis involving the cerebrum and cerebellum. there was a marked segmental loss of granular cells and purkinje cells, as well as segmental atrophy of the molecular layer in the cerebellum. protozoal merozoites and schizonts ...

a 16-year-old female japanese cat was presented with a single mammary-gland nodule approximately 3 cm in diameter. histologically, the nodule consisted of necrotizing granulomatous panniculitis, vasculitis, and mastitis, and contained free and clustered protozoal organisms. the organism was present in the cytoplasm of macrophages, fibroblasts, endothelial cells, and mammary-gland epithelia. the organism was positive for anti- toxoplasma gondii and anti- neospora caninum antibodies. electron micr ...

internal hydrocephalus and associated periventricular encephalitis in a young fox.

marked lateral ventricular enlargement associated with atrophic cerebral cortex and periventricular encephalitis is described in a 2-month-old fox affected by disorientation, generalized ataxia, difficulty in walking, circling, and blindness. clinical conditions progressed to stupor and spontaneous death within a few days. at necropsy, severe inflammatory and necrotizing lesions were observed in periventricular sites associated with diverticula and cleft formation in perithalamic areas and rhine ...

first israeli neospora caninum isolates were obtained from brain tissues of aborted fetuses (ncis491 and ncis580) from dairy farms endemic for neosporosis and maintaining cattle on zero grazing. tissues from different parts of the fetus brains were used to infect vero cells. tachyzoites of n. caninum were first observed in cultures from days 30 and 32 after infection. to confirm the identity of the isolated parasites, dna extracts from brains and cultures were tested by pcr with specific primers ...

many immunological aspects of pregnancy, such as the role played by gamma interferon (ifn-gamma) in abortion, are not well understood. neospora caninum is an intracellular protozoan considered to be among the main causes of abortion in cattle worldwide. the present study analyzes the interaction between ifn-gamma production and n. caninum infection in naturally infected pregnant cows. data were obtained from 126 pregnant cows: 86 seropositive and 40 seronegative for the parasite. pregnancy diagn ...

fecal and serological survey of neospora caninum in farm dogs in costa rica.

to detect oocysts of neospora caninum in dog feces and to determine the excretion pattern in dogs from specialized dairy farms in costa rica, a total of 265 fecal samples from 34 dogs were collected at intervals from february to august 2005. fecal samples were examined for n. caninum-like oocysts microscopically, by dna detection using the polymerase chain reaction (pcr), and by bioassay. n. caninum dna was detected by pcr in four fecal samples, twice from one dog, but oocysts were not detected ...